force checkpoint on pie and up

Author: Krzysztof Borowy

android/src/main/java/com/reactnativecommunity/asyncstorage/AsyncLocalStorageUtil.java

@@ -9,13 +9,17 @@
 
 import javax.annotation.Nullable;
 
+import java.io.File;
 import java.util.Arrays;
 import java.util.Iterator;
 
 import android.content.ContentValues;
+import android.content.Context;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
+import android.os.Build;
 import android.text.TextUtils;
+import android.util.Log;
 
 import com.facebook.react.bridge.ReadableArray;
 
@@ -142,4 +146,36 @@ private static void deepMergeInto(JSONObject oldJSON, JSONObject newJSON)
       }
     }
   }
+  /**
+   * From Pie and up, Android started to use Write-ahead logging (WAL), instead of journal rollback
+   * for atomic commits and rollbacks.
+   * Basically, WAL does not write directly to the database file, rather to the supporting WAL file.
+   * Because of that, migration to the next storage might not be successful, because the content of
+   * RKStorage might be still in WAL file instead. Committing all data from WAL to db file is called
+   * a "checkpoint" and is done automatically (by default) when the WAL file reaches a threshold
+   * size of 1000 pages.
+   * More here: https://sqlite.org/wal.html
+   * <p>
+   * This helper will force checkpoint on RKStorage, if Next storage file does not exists yet.
+   */
+  public static void verifyAndForceSqliteCheckpoint(Context ctx) {
+    File nextStorageFile = ctx.getDatabasePath("AsyncStorage");
+    File currentStorageFile = ctx.getDatabasePath(ReactDatabaseSupplier.DATABASE_NAME);
+    boolean isCheckpointRequired = Build.VERSION.SDK_INT >= Build.VERSION_CODES.P
+            && !nextStorageFile.exists()
+            && currentStorageFile.exists();
+    if (!isCheckpointRequired) {
+      Log.i("AsyncStorage_Next", "SQLite checkpoint not required.");
+      return;
+    }
+
+    try {
+      ReactDatabaseSupplier supplier = ReactDatabaseSupplier.getInstance(ctx);
+      supplier.get().execSQL("PRAGMA wal_checkpoint");
+      supplier.closeDatabase();
+      Log.i("AsyncStorage_Next", "Forcing SQLite checkpoint successful.");
+    } catch (Exception e) {
+      Log.w("AsyncStorage_Next", "Could not force checkpoint on RKStorage: " + e.getMessage());
+    }
+  }
 }

android/src/main/java/com/reactnativecommunity/asyncstorage/AsyncStoragePackage.java

@@ -1,19 +1,21 @@
 /**
  * Copyright (c) Facebook, Inc. and its affiliates.
- *
+ * <p>
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
 
 package com.reactnativecommunity.asyncstorage;
 
 import android.util.Log;
+
 import com.facebook.react.ReactPackage;
 import com.facebook.react.bridge.JavaScriptModule;
 import com.facebook.react.bridge.NativeModule;
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContext;
 import com.facebook.react.uimanager.ViewManager;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -29,6 +31,7 @@ public List<NativeModule> createNativeModules(ReactApplicationContext reactConte
                 Class storageClass = Class.forName("com.reactnativecommunity.asyncstorage.next.StorageModule");
                 NativeModule inst = (NativeModule) storageClass.getDeclaredConstructor(new Class[]{ReactContext.class}).newInstance(reactContext);
                 moduleList.add(inst);
+                AsyncLocalStorageUtil.verifyAndForceSqliteCheckpoint(reactContext);
             } catch (Exception e) {
                 String message = "Something went wrong when initializing module:"
                         + "\n"